Separable attachment plug



March u 1924., y ma `N. W. NUTT SEPARABLE ATTACHMENT PLUG jim Original Filed Sent. l, 1921 A TTORNE Y.

p provide for certain relined features of con- NOAN W. NUTT, OF TRENTON, NEW JERSEY.

Meer

sErLn arrac f @riginal application led September 1, 1921, Serial No. 497,518. Divided and this application nle. January 12, 1923. vSerial No. 812,189.

To all whom t may concern.'

a Be `it known that I, NORMAN W. NUTT, a citizen of the United States, residing at Trenton, in the county of Mercer and State of New Jersey, have invented certain new and useful Improvements in Separable Attachment Plugs, of which the following is a specification.

This invention relates to improvements in separable attachment plugs, yis a division of my copending application Serial Number 497518 and-has for its principal object to struction and arrangement of the parts thereof, whereby to provide for more ecient electrical connection between the current conducting parts or contacts thereof.

- an interlocking of the attachment Another object of the invention is to provide for certain novel forms of current conducting parts or contacts for separable attachment plugs, and which are adapted for 'cooperation or engagement one with the other, whereby to prevent free separation thereof, and to otherwise effect a positive and effective' electrical contact between the same, when'the. separable parts plugs are joined together.

With the foregoing and other objects in View, the invention resides in the certain novel and usefulconstruction and arrangement of parts, as well be hereinafter more fully described, set forth in the appendedl claim, and .illustrated in the accompanying drawings, in which: l LFigure 1 is a sectional view ofthe plug the same being taken onthe line 1-1"`o Y.

Fi `e 2,7..v -igure 2 1s of the base portlonpf the latter form ofplug,

\. Figure-3 is al sectionalI view of thebase portion of 4the plug, the same being taken on the line 3-3 of Figure 2,

a bottom view Figure 4 is a sectionalview corresponding to that of Figure 1, but showing the separa.` vble parts of the plu-g as joined together into operatrve re1ation-cne with respect to the other,

Figure 5 is a front and side elevation of the `contact memberto be electrically connected to the screwl shell of the base porltion of the modified form of the plug, and 6' is a front andside elevatlon of the center contact or member of the base portion :of the latter plug.

It@ Referring` the drawing, ywherein similar characters of reference designate corresponding .partsl throughout the several views thereof, the numeral 10 indicates the cap portion of the attachment plug, and the numeral 11 the base portion thereof, both portions 10 and 11 being'formed of an insulating material or composition, such as porcelain or the like.

The top portion 10 is provided with a centrally disposed opening 12 through which the usual conductors or leads (not shown) are insertedl for attachment to the usual contact vscrews 13 passed downwardly through recesses 14 formedin the cap portion to either side of the central opening 12,

the recesses 14 being, after the screws 13 are positioned therein, filled with a sealingmaterial, whereby the vlatter are held against movement or displacement from operative position. The lower face of the cap 10is preferably concaved or otherwise suitably recessed as at 15 to admit of the conductors at its upper end 17, as of a diameter correv.spending to that ofthe cap portion 10, and

-1s exteriorly reduced in -dlameter inwardly from itsy lowerv end 18 to receive thereon 'a usual form of threaded metal shell 19,'adapted for'enga ment with the coondin ly threaded shll of a lamp bracket or the' lzigke y(not shown); 'The base portion is formed to provide. a pair of channel ways 21 and 22 extending longitudinally thereof and spaced .10@

diametrically apart onefrom the other/in a "manner to be aligned with the contact fingers 16 of the cap portion 10, which are adapted to be inserted within the same. The base or plug portion 11 is further formed to rovide a central cylindrical portion 23, w ich 1s projected outwardly o the reduced end portion thereof, and the free end of this portion is formedl substantially -frustro-conical as at 24, se that its extreme outer en d is of sub'- of a contact bolt or screw 25, which is'passed 4inwardly of a bore formed centrally and longitudinally in the portion 23, the reduced end portion 24, of the latter, being countersunk to seat the head 26 of the bolt or screw 25 and dispose the same flush in the plane of the end face of the portion 23, the inner end of the bolt or screw 25 being secured within the recess 27 by means of a nut 28.

The contact .member associated with the channel way 21 comprises a metal strip having an angularl'y bent outer end portion 46 which is apertured as at 47 for engagement under the heads of the center screw 25, and

ithe leg portion 48 of the strip, as shown in Figure 6, is stamped out at its opposite side edges to provide pairs of end portions 49, which are bent outwardly from one side of the leg portion 48, and have theirfree ends bent asat 50 to normally lie parallel to the latter portion 48. The inner free end portion 51 of the leg portion 48 is similarly bent to correspond to the angular disposition of the tongues 49, and immediately inward of the bends thereof the leg portion 48 is provided with a projection 52, which extends outwardly' from the face of the same in a direction opposite to that of the tongue portions 49. The leg portion 53 of the contactmember arranged within the channel way 22, as in Figures 1 and 4, may be formed correspondingly with respect to the leg portion 48 of the other of the modified forms of thev contact members, or the same will .be constructed inthe manner as shown in Figure 5, wherein tongue portions 54 are struck outwardly from the longitudinal center of the leg to one side thereof, an d have their free end portions 55 bent to lie in a planeV paralleloto the adjacent face of the latter. The inner free end of the leg portion 48 is angularly bent as at 56 in -a direction corresponding to that of the tongues 54, and immediately inward of the portion 56, the 1 eg portionv is provided with a raised pro- ]ection or the like 57, which extends 'there- 'from in a direction opposite to Vthat of the tongues 54. The outer end ofthe leg portion 53 is angularly bent to provide a subst-antially semi-circular portion 58, corresponding to the portion 37 of the other form of the contact member or 'aw, which. is apertured for engagement under the head of the bolts orl screws 38 and A39, and clamped thereby into electrical contact with the pro-y jecting 'portion 40 of the screw shell 19 of the plug.

With the parts of the devices assembled as indicated'for the same, and when it is desired to couple the cap portion 1'0 onto the base or plug portion 11, the contact fingers 16 of thev former .are inserted into the complementalchannelways 2 1 and 22 of the plug and between the contact members and onewall of the cap member are inserted into the complei mental ends of the Channel ways 21 and 22, the tongues 51, 56 act to guide the finger 16 along the flat side faces of the legv portions 48, 53, placing the tongues 5l, 56 under tension to assure of good electrical contact between the fingers 16 and the leg portions 48, 53. When the fingers 16 are inserted in the channelways 21 and 22, the tongues 51, 56 are shifted to engage a wall of the said channelways, as shown in Fig. 4. The fingers 16 are provided with openings 59, formed inwardly from the free ends thereof, and, the projections 52, 57 of the contact jaws, will snap into such engagement, whereby to prevent accidental separation of the cap member l0 from the base or plug portion 11, and to otherwise make it necessary to subject the parts to a Slight pulling strain in opposite directions to accomplish the separation thereof when desired.

The extremely important and valuable features of the invention primarily resides ment of the tongue portions of the base conl tact members or jaws acting to retain the latter parallel to the opposite walls Aof the chann ways 21 and 22, whereby to effect a. rubbing contact between the faces of the same' opposed to those of the cap contact fingers 16; and in the angularly bent or flared end portions of the base contactmembers for guiding the cap contact fingers 16 into proper contacting relation with res ect to the base-contact members or jaws. t is to be noted also that the resiliency of the base contact members or jaws assures of the positive contact of the same with the cap contact fingers 16 irrespective of the fact as to whether or not the latter are straight or have become slightly irregular in shape during the constant use ofthe same. By making the contact members or jaws from single l ri idity in construction as to be durable and e cient in use. l

'It is well'understood that, while the preferred embodiments of the devices have been described and illustrated herein in specific terms. and details Aof construction .and arrangement, various changes in and modifications of the same may be lresorted to Without departing from the spirit ofthe invention, or the scope of the claim appended hereto. i Y

Having thus fully described the invention, what is claimed, is A contact member for separable attachment plugs, comprising a strip of sheet -metal having a plurality of tongue portions displaced from and to one side of the opposite longitudinal edges thereof and arranged to .tension the strip into operative contacting position, the free end portion of the said strip being angularly bent in a manner to act as a guide for the cooperative engagement with the strip of a complementally disposed Contact member, and a project-ion formed on said strip inwardly from the angularly bent end portion thereof and on the side of the same opposite to that from which the tongue portions are projected, said projection being adapted for engagement in an aperture formed in the said complemental contact member for retaining the same in cooperative contacting engagement with the said strip. y

. In testimony whereof, I ax my signature hereto.A

NORMAN W. NUTT. 

